Re: Problems decoding GRIB2 GFS Ensemble grids

Kevin and all...

I added the PD# 2 and 12 entries (eg Derived forecast based on all
ensemble members at a point in time, and Derived forecast based on all
ensemble members for
a time interval) for the gavg and gspr files as well and updated the
tables posted.

Also, for the 5.9.4 distribution, I have added a %ens% file name
template to the dcgrib2 decoder so that the individual members, average,
spread etc can
be written to individual files using a single filename pattern.  The
GEMPAK 
ens_xxx() functions will enable you to compute derived and probabalistic
quantities
based on the individual members using the GDFILE={file(s)} syntax. I am
adding information to the tutorial and examples pages to illustrate
these capabilities.

Steve Chiswell
Unidata User Support

On Wed, 2006-10-11 at 14:36 +0000, Kevin R. Tyle wrote:
> Thanks again Steve.  I can now decode the control and perturbation fields. 
> However, it looks like the tables need to be further expanded so they can 
> decode the "geavg" and "gespr" bulletins.
> 
> Regards,
> 
> Kevin
> 
> ______________________________________________________________________
> Kevin Tyle, Systems Administrator               **********************
> Dept. of Earth & Atmospheric Sciences           address@hidden
> University at Albany, ES-235                    518-442-4578 (voice)
> 1400 Washington Avenue                          518-442-5825 (fax)
> Albany, NY 12222                                **********************
> ______________________________________________________________________
> 
> On Tue, 10 Oct 2006, Steve Chiswell wrote:
> 
> > Kevin,
> >
> > The most recent version of dcgrib2 (5.9.3) will store the GRIB2 data in
> > the grid file without unpacking the data block, making the GEMPAK file
> > much smaller, and the
> > decoding process much faster. The older GEMPAK distributions will not be
> > able to read those decoded files however, since they do not know how to
> > unpack the GRIB2 data block, so if you use the 5.9.3 decoder, you would
> > want to upgrade the other programs as well, or recompile the dcgrib2
> > program from 5.9.3 to
> > use the previous packing method for the data- but you may find that
> > unpacking and
> > repacking the data in realtime is quite a load on the LDM pqact
> > processing (otherwise, you can use nagrib2 outside of the LDM which will
> > be compatible
> > with the previous versions).
> >
> > I'll add a command line flag to the 5.9.4 dcgrib2 to allow you to select
> > the storage
> > method for backward compatibility.
> >
> > Steve Chiswell
> > Unidata User Support
> >
> >
> >
> >
> > On Tue, 2006-10-10 at 01:24 +0000, Kevin R. Tyle wrote:
> >> Hi Steve,
> >>
> >> Thanks for the updated files.  I can now get it to work using the
> >> GEMPAK5.9.3 version of dcgrib2 using the corrected tables.  However, even
> >> with the updated tables, versions 5.9.1 and 5.7.4 of dcgrib2 still do not
> >> decode.  Perhaps I shall just recompile dcgrib2 for use in these two
> >> distributions (which are still in operational use here) unless you have
> >> another idea.
> >>
> >> Thanks,
> >>
> >> Kevin
> >>
> >> ______________________________________________________________________
> >> Kevin Tyle, Systems Administrator               **********************
> >> Dept. of Earth & Atmospheric Sciences           address@hidden
> >> University at Albany, ES-235                    518-442-4578 (voice)
> >> 1400 Washington Avenue                          518-442-5825 (fax)
> >> Albany, NY 12222                                **********************
> >> ______________________________________________________________________
> >>
> >> On Mon, 9 Oct 2006, Steve Chiswell wrote:
> >>
> >>> Kevin,
> >>>
> >>> The GEMPAK GRIB2 parameter tables use 4 numbers to define the parameter
> >>> name.
> >>> The 4th column is the parameter template, which allows different names
> >>> to be assigned depending on the type ofaccumulation, average, ensemble
> >>> etc. used.
> >>> Log messages from dcgrib2 under "decode_grib2 -34" about unknown
> >>> parameter
> >>> mean that the decoder tables need to be updated (in particular, entries
> >>> for ensemble PDTs 1 and 11 in column 4).
> >>>
> >>> Updated g2varswmo2.tbl and g2varsncep1.tbl tables which include the
> >>> ensemble entries can be downloaded from:
> >>>
> >>> http://www.unidata.ucar.edu/downloads/gempak/tables/
> >>>
> >>> Steve Chiswell
> >>> Unidata User SUpport
> >>>
> >>>
> >>>
> >>>
> >>> On Mon, 2006-10-09 at 21:26 +0000, Kevin R. Tyle wrote:
> >>>> I've been attempting to decode the GFS ensemble data from the "new"
> >>>> CONDUIT NCEP ftp directory, as described in
> >>>> http://www.unidata.ucar.edu/data/conduit/ldm_idd/ensemble_files.html#GRIB2.
> >>>> However, dcgrib2 is not able to determine the GEMPAK parameter name, and
> >>>> no GEMPAK grid is created.  I've attached the output from the dcgrib2 
> >>>> log.
> >>>>
> >>>> gec00.t12z.pgrb2af48
> >>>>
> >>>> Any ideas?
> >>>>
> >>>> Thanks,
> >>>>
> >>>> Kevin
> >>>>
> >>>> ______________________________________________________________________
> >>>> Kevin Tyle, Systems Administrator               **********************
> >>>> Dept. of Earth & Atmospheric Sciences           address@hidden
> >>>> University at Albany, ES-235                    518-442-4578 (voice)
> >>>> 1400 Washington Avenue                          518-442-5825 (fax)
> >>>> Albany, NY 12222                                **********************
> >>>> ______________________________________________________________________
> >>> --
> >>> Steve Chiswell <address@hidden>
> >>> Unidata
> >>>
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> >>>
> >>
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> > -- 
> > Steve Chiswell <address@hidden>
> > Unidata
> >
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-- 
Steve Chiswell <address@hidden>
Unidata